• 한국자기학회지
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• 제15권1호
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• pp.37-41
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• 2005

70% 이사의 결정질 마그키타이트를 함유한 산화철 폐촉매를 Attritor에서 미립화하고 계면활성제 종류별로 마그네타이트 미립자를 피복하여 물에 분산하므로 수상 자성유체를 제조하였다. Attritor를 사용하여 볼 : 시료 : 물의 중량비가 최적조건인 2000 : 100 : 100에서 60시간 동안 산화철 폐촉매를 미립화하고, 여기에 계면활성제 oleic acid 20 ml를 넣고 한시간 동안 가열한 후 물에 분산하므로 자화값이 22emu/g인 수상 자성유체를 제조하였다.

• Advances in environmental research
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• 제5권1호
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• pp.61-77
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• 2016

$NanoTiO_2$ was synthesized by ultrasonication assisted sol-gel process and subjected to iron doping and carbon-iron codoping. The synthesized catalysts were characterized by XRD, HR-SEM, EDX, UV-Vis absorption spectroscopy and BET specific surface area analysis. The average crystallite size of pure $TiO_2$ was in the range of 30 - 33 nm, and that of Fe-$TiO_2$ and C-Fe $TiO_2$ was in the range of 7 - 13 nm respectively. The specific surface area of the iron doped and carbon-iron codoped nanoparticles was around $105m^2/g$ and $91m^2/g$ respectively. The coupled semiconductor photo-Fenton's activity of the synthesized catalysts was evaluated by the degradation of a cationic dye (C.I. Basic blue 9) and an anionic dye (C.I. Acid orange 52) with concurrent investigation on the operating variables such as pH, catalyst dosage, oxidant concentration and initial pollutant concentration. The most efficient C-Fe codoped catalyst was found to effectively destruct synthetic dyes and potentially treat real textile effluent achieving 93.4% of COD removal under minimal solar intensity (35-40 kiloLUX). This reveals the practical applicability of the process for the treatment of real wastewater in both high and low insolation regimes.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1016-1019
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• 2005

We studied the density control of carbon nanotubes (CNTs) which were grown on the iron nanoparticles prepared from iron-acetate [$Fe(II)(CH_3COO)_2$] solution using freeze-dry method. The density of CNTs was controlled for the enhancement of field emission. The patterning process of iron-acetate catalyst-layer for the fabrication of electronic device was simply achieved by using alkaline solution, TMAH (tetramethylammonium hydroxide). We applied this patterning process of catalyst layer to formation of the electron emitter with under gate type triode structure.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1455-1458
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• 2005

We studied the density control of carbon nanotubes (CNTs) which were grown on the iron nanoparticles prepared from iron-acetate $[Fe(II)(CH_3COO)_2]$ solution using freeze-dry method. The density of CNTs was controlled for the enhancement of field emission. The patterning process of iron-acetate catalyst-layer for the fabrication of electronic device was simply achieved by using alkaline solution, TMAH (tetramethylammonium hydroxide). We applied this patterning process of catalyst layer to formation of the electron emitter with under-gate type triode structure.

• Advances in environmental research
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• 제4권4호
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• pp.263-271
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• 2015

In this study, the effect of initial nitrate loading on nitrate removal and byproduct selectivity was evaluated in a continuous system. Nitrate removal decreased from 100% to 25% with the increase in nitrate loading from 10 to $300mg/L\;NO_3-N$. Ammonium selectivity decreased and nitrite selectivity increased, while nitrogen selectivity showed a peak shape in the same range of nitrate loading. The nitrate removal was enhanced at low catalyst to nitrate ratios and 100% nitrate removal was achieved at catalyst to nitrate ratio of ${\geq}33mg\;catalyst/mg\;NO_3-N$. Maximum nitrogen selectivity (47%) was observed at $66mg\;catalyst/mg\;NO_3-N$, showing that continuous Cu-Pd-NZVI system has a maximum removal capacity of 37 mg $NO_3{^-}-N/g_{catalyst}/h$. The results from this study emphasize that nitrate reduction in a bimetallic catalytic system could be sensitive to changes in optimized regimes.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.267-270
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• 2014

Since contaminants of syngas obtained from the biomass gasification are removed, the syngas is clean fuel. In this study a high-efficiency energy production system is developed. The system produces electricity using a waste pressure and feeds a low-pressure steam to Dyeing industrial complex. Also, iron oxide derived from dyeing sludge is utilized as a self-catalyst to reform a tar and reduce a tar emission from gasifier. This system increases the amount of syngas and finally achieves a highly efficient gasification.

• Environmental Engineering Research
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• 제25권1호
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• pp.36-42
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• 2020

Fenton process is one of the most effective advanced oxidation processes for the removal of pollutants from wastewater. In this study, while ferrous iron was used in conventional Fenton process (CFP); nano-sized iron(II, III) oxide was experienced in modified Fenton process (MFP) as a new catalyst alternative. In order to enhance their oxidation efficiencies, both CFP and MFP were combined with ultrasonication at 53 kHz fixed frequency. Thus, the influences of both catalyst iron species and ultrasonication on color and chemical oxygen demand (COD) removals from synthetic textile wastewater including Maxilon Red GRL 200% dyestuff were investigated experimentally. While the COD and color removal rates were found as 72.5% and 69.7% via CFP; they were 87% and 75.8% by ultrasonicated CFP, respectively. The color and COD removals were 40.6% and 64.8% via MFP, and 49.9 and 73.1% by ultrasonicated MFP, respectively. Therefore, it was found that the simultaneously usage of ultrasonication with CFP and MFP was improved the COD and color removal efficiencies and oxidation rates even at lower H₂O₂ dosages, compared to individual CFP and MFP. Moreover, the color and COD removal kinetics were also modelled mathematically and compared in the study.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 1998년도 봄 학술발표회 프로그램
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• pp.157-159
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• 1998

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.670-673
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• 2002

We have investigated the catalyst effect on the growth and structure of CNTs using thermal chemical vapor deposition. The respective growth rate of CNTs shows that the performance of catalysts is in the order of nickel (Ni)>cobalt (Co)>iron (Fe). The average diameter of CNTs follows the sequence of Fe, Co, and Ni catalysts. The structure of CNTs reveals almost same morphology regardless of catalyst but the crystallinity of CNTs is largely dependent on catalyst. The crystallinity of CNTs synthesized from Fe catalyst is higher than that from Ni or Co catalyst. We demonstrate that the growth rate, the diameter, and the crystallinity of CNTs can be manipulated by selecting the catalysts.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.349-354
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• 2005

It is interesting to discover the reaction kinetics of the newly developed molybdenum containing catalysts. The dissociation/adsorption of nitrogen on molybdenum surface is known to be structure sensitive, which is similar to that of nitrogen on iron surface. The rates over molybdenum nitride catalysts are increased with the increase of total pressure. This tendency is the same as that for iron catalyst, but is quite different from that for ruthenium catalyst. The activation energies of the molybdenum nitride catalysts are almost on the same level, although the activity is changed by the addition of the second component. The reaction rate is expressed as a function of the concentration of reactants and products. The surface nature of $CO_3Mo_3N$ is drastically changed by the addition of alkali, changing the main adsorbed species from $NH_2$ to NH on the surface. The strength of $NH_x$ adsorption is found to be changed by alkali dopping.